JPH0659833B2 - Vehicles with electric power steering - Google Patents

Description

The present invention relates to a vehicle with electric power steering such as a forklift truck equipped with electric power steering.

(Prior Art) Conventionally, as a forklift truck with hydraulic power steering, for example, “Nissan Service Weekly Report 434” is used.
No. (F-18) "(published by Nissan Motor Co., Ltd. in February 1981) on page 109 is known.

This conventional forklift truck is designed to obtain assist power to assist the steering force by hydraulic pressure from the hydraulic cylinder.Maintenance is not required except when oil leak or other failure occurs, but hydraulic piping is required. There was also a need for a highly precise and delicate device such as a hydraulic control valve. Also, for the hydraulic power steering as described above,
There is known an electric power steering in which an assist power can be directly obtained by an electric power steering motor as described in Japanese Utility Model Laid-Open No. 60-144572.

Therefore, if an electric power steering is installed instead of the hydraulic power steering of the forklift truck with hydraulic power steering described above, and a forklift truck with electric power steering alignment is used, hydraulic piping and hydraulic control valves are not required and The power steering motor is a very suitable vehicle because the wiring is easy.

(Problems to be Solved by the Invention) However, in the case of a forklift truck with electric power steering, an electric power steering motor provided integrally with a power assist mechanism is different from a hydraulic pump motor in a steering force transmission system. It is placed on the way and at a position where it does not interfere with other members, and is specifically placed between the inner wall of the motor box housing the cargo handling pump motor and the traveling motor (or engine). Therefore, the electric power steering motor is arranged between the upper frame (battery support frame or the like) and the lower frame (center cross member or the like).

However, in the electric power steering motor, it is necessary to inspect and convert the motor brush, which is a consumable part, at predetermined intervals, and therefore it is necessary to provide an opening at a position where inspection and replacement work can be performed.

As a position to provide this opening, there is a plan to first provide it in the upper frame, but in this case, it is necessary to remove the battery and seat etc. mounted in the upper frame before performing the work. There is also a plan to install it in this case, but in this case the work will be carried down and the workability will be poor, and mud and stones will enter from the opening when traveling, and if the lower frame is a reinforcing member, the opening Will reduce the strength.

(Means for Solving Problems) The present invention has been made for the purpose of solving the above-mentioned problems, and in order to achieve this object, the present invention is provided at a lower position of the vehicle body. An electric power steering system including a cargo handling pump motor housed in a motor box, a power assist mechanism provided midway in a steering force transmission system from a steering wheel, and an electric power steering motor as an assist power generating actuator. In a vehicle with a
The left and right side walls, the upper wall, the lower wall, and the inner wall of the inner portion facing the power assist mechanism are formed.The outer portion of the motor box is a box opening, and the inner wall of the modabox has an opening that is always open. A pump motor for cargo handling is provided in a box space surrounded by the wall surface of the motor box, and an electric power steering motor is disposed at a position facing the opening of the inner wall and adjacent to the pump motor for cargo handling. Was adopted.

(Operation) When inspecting or replacing the motor brush of the electric power steering motor in the vehicle with electric power steering according to the present invention, the cargo handling pump motor arranged in the box space from the box opening on the outer side of the motor box. Pull out or remove. When the work of removing the pump motor for cargo handling is performed, the inner wall of the motor box and the electric power steering motor are exposed to the box opening, so that the electric power steering motor arranged at a position facing the opening of the inner wall is The motor brush can be inspected or replaced through the box opening and the opening that is always open.

Therefore, the inspection or replacement work of the motor brush of the electric power steering motor can be performed with good workability in a short time, and at the same time, the inspection or replacement work of the motor brush of the cargo handling pump motor can be performed.

(Examples) Hereinafter, examples of the present invention will be described in detail with reference to the drawings. In describing this embodiment, a battery forklift truck with electric power steering will be taken as an example.

First, the configuration of the embodiment will be taken as an example.

The electric power steering A applied to the battery forklift truck of the embodiment is, as shown in FIG.
As a steering force transmission system, a steering wheel 10, a steering shaft 11, a steering gear 12, a pitman arm 13, a drag rod 14, a bell crank 1
5, tie rods 16 and 17, and axle hubs 18 and 19.

The steering shaft 11 is connected by a universal joint 20.
A tilt mechanism 21 having a lock lever 21a is provided in the section.

One end of the drag rod 14 is a pitman arm 1
3, and the other end is a power assist mechanism 30 described later.
The power screw rod 36 is connected to the bell crank 15 through the power screw rod 36.

The bell crank 15 is rotatably provided on the axle center housing 22 by a bell crank pin 23.

Although not shown, the axle hubs 18 and 19 are provided with steering wheels.

The power assist mechanism 30 provided in the middle of the above steering force transmission system includes a mounting base 31, a universal joint 32, a power screw tube 33, a power assist housing 34, a dust cover 35, a power screw rod 36, a motor flange 37, an electric power. A steering motor 38 is provided.

The mounting base 31 is bolted to a bracket 41 fixed to the back surface of a motor box 40, which will be described later, and the power screw tube 33, the electric power steering motor 38, and the like are mounted on the drag rod 1 associated with steering.
Universal joint 3 so that it can follow the displacement of 4
It is connected by 2.

In the drag rod 14 shown in FIG. 2, the solid line position is the rod position when traveling straight, the upper right virtual line position is the rod position when turning to the right, and the lower right virtual line position is the rod position when turning to the left. 2 shows the motor flange 37 and the cargo handling pump motor 50 in a slight interference state in FIG. 2, but interference is avoided due to the positional relationship in the vehicle front-rear direction.

Inside the power screw tube 33 and the power assist housing 34, a power screw rod 36 having a ball screw groove is provided, and the assist power from the electric power steering motor 38 is
Reduction gear (not shown) → screw ball case → power screw rod 36 after passing screw ball
Is transmitted to.

The electric power steering motor 38 is a motor bolted to a motor flange 37 provided at an angle of 45 to 50 degrees with respect to the power screw tube 33. The electric power steering motor 38 has a motor brush at a rearward outward position. An inspection unit 38a is provided.

The electric power steering motor 38 is provided obliquely above the power screw tube 33, as shown in FIG.
This is to secure a space for disposing the drag rod 14 between and.

Next, the in-vehicle layout of the power assist mechanism 30 will be described with reference to FIGS.

As a peripheral member adjacent to the power assist mechanism 30,
There are a motor box 40, a cargo handling pump motor 50, a battery unit 60, a center cross member 70, and a traveling motor 80.

The motor box 40 is composed of left and right side walls 42 and 43, which are parts of the vehicle body frame, an upper wall 44, a lower wall 45, and an inner wall 46 at a lower position of the vehicle body. A box space for storing 50 is formed.

An opening / closing cover 47 is provided at the box opening on the outer side of the motor box 40, and the electric power steering motor 3 is provided on the inner wall 46 of the motor box 40.
No. 8 is provided with an opening 46a that is always open for motor brush wear inspection and motor brush replacement.

The electric power steering motor 38 of the power assist mechanism 30 is arranged so as to face the opening 46a.

The cargo handling pump motor 50 includes the motor box 4
No. 0 is housed in the longitudinal direction of the vehicle, and the motor shaft is provided with a cargo handling pump 51 having a gear pump structure or the like. The motor is supported by the mount insulator 52 on the motor box 40 at four points.

The support bracket 53 provided with the mount insulator 52 is fixed to the U channels 54 and 55 fixed to the lower wall 45 of the motor box 40 by two connecting bolts 56 and 57 on the front side of the vehicle. The rear side of the vehicle is fixed by a single fulcrum bolt 58, and the cargo handling pump motor 50 is formed so as to be rotatable and drawn out by rotating around the fulcrum bolt 58.

The battery unit 60 includes a traveling motor 80, a cargo handling pump motor 50, and an electric power steering motor 3.
Power assist mechanism 3 for power source of vehicle electrical equipment such as 8
0, the motor box 40, the traveling motor 80, and the like.

The battery unit 60 is supported by a battery support 61 shown in FIG. 2 and a battery support frame (not shown).

The center cross member 70 is a member provided to serve both as a reinforcement member in the vehicle width direction and a protection member for the power assist mechanism 30, and one end of the center cross member 70 is
It is fixed to the inner wall of the motor box 40.

The traveling motor 80 is a drive unit that outputs a traveling driving force of the vehicle, and is arranged inside the power assist mechanism 30 at a substantially central position of the vehicle body frame.

Next, the operation of the embodiment will be described.

The inspection or replacement work of the motor brush of the electric power steering motor 38 is performed in the following procedure (see FIG. 4).

・ Remove the open / close cover 47.

• Loosen the fulcrum bolt 58, remove the other connecting bolts 56 and 57, and then remove the motor cable.

As shown in FIG. 4, the cargo-handling pump motor 50 is rotated and pulled out toward the front centering on the fulcrum bolt 58.

-Insert a hand from the work space formed by pulling out the cargo handling pump motor 50, take out the brush from the brush inspection portion 38a of the electric power steering motor 38,
Check to see if the motor brush has exceeded its wear limit and if so, replace with a new motor brush.

When inspecting the motor brush of the electric power steering motor 38, the inspecting operation of the motor brush of the cargo handling pump motor 50 pulled out to the front may be performed at the same time.

When the inspection or replacement work is completed, the cargo handling pump motor 50 is returned to its original position, the coupling bolts 56, 57 and the fulcrum bolt 58 are tightened, and the opening / closing cover 47 is attached to complete the work.

As described above, the battery forklift with electric power steering of the embodiment has the following effects.

The inspection or replacement work of the motor brush can be performed without removing the battery unit 60, the seat, or the like, or digging under the vehicle.

When inspecting or replacing the motor brush of the electric power steering motor 38, it is possible to simultaneously inspect or replace the motor brush of the cargo handling pump motor 50 that is pulled out toward the front during the operation.

Since the cargo handling pump motor 50 is rotated and pulled out to the front, it is not necessary to remove the cargo handling pump motor 50 or the like, and neither a crane nor a large number of manpower is required when inspecting or replacing the motor brush. .

Although the embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and the present invention can be applied even if there is a design change or the like within a range not departing from the gist of the present invention. included.

For example, although the example in which the invention is applied to the battery forklift truck is shown, the invention can be applied to an engine forklift truck equipped with an engine instead of the traveling motor.

Further, in the embodiment, the preferable example in which the cargo handling pump motor is pulled out to the front by the rotation is shown, but in addition, it may be pulled out toward the front by sliding, or the cargo handling pump motor may be completely removed from the motor box and lowered. It is included even if it is made.

(Effects of the Invention) As described above, in the vehicle with electric power steering according to the present invention, the motor box includes the left and right side walls, the upper wall, the lower wall, and the inner wall of the inner portion facing the power assist mechanism. The outer part of the motor box is a box opening, the inner wall is provided with an opening that is always open, and the cargo handling pump motor is arranged in a box space surrounded by the wall surface of the motor box. Since the electric power steering motor is arranged in a position facing the opening and adjacent to the cargo handling pump motor, it is possible to check or replace the motor brush of the electric power steering motor from the motor box side in a short time. The workability can be improved, and at the same time, the motor brush of the cargo handling pump motor can be inspected or replaced. The effect that can be obtained is obtained.

[Brief description of drawings]

FIG. 1 is a perspective view of an essential part showing a battery forklift truck with electric power steering according to an embodiment of the present invention.
FIG. 3 is a sectional view showing the layout of the power assist mechanism in the forklift truck of the embodiment, FIG. 3 is a side view from the motor box side of the forklift truck of the embodiment, and FIG. 4 is a motor brush of the forklift truck of the embodiment. It is a top view for explaining inspection or exchange work. 10 ... Steering wheel 30 ... Power assist mechanism 38 ... Electric power steering motor 40 ... Motor box 46 ... Inner wall 46a ... Opening 50 ... Cargo handling pump motor

Claims (1)

[Claims] 1. A pump motor for cargo handling, which is housed in a motor box provided at a lower position of a vehicle body, and a power assist mechanism provided in the middle of a steering force transmission system from a steering wheel. In an electric power steering motor-equipped vehicle including: an electric power steering motor, the motor box includes left and right side walls, an upper wall, a lower wall, and an inner wall of an inner portion facing the power assist mechanism. The outer part is the box opening,
An opening that is always open is provided in the inner wall, a pump motor for cargo handling is arranged in a box space surrounded by the wall surface of the motor box, and the pump motor for cargo handling is located adjacent to the opening in the inner wall and adjacent to the pump motor for cargo handling. A vehicle with electric power steering, characterized in that an electric power steering motor is arranged at a position where